@Polinalkrimizei
Can you paste error from Blender console (Window -> Toggle System Console)? Also, please try to delete indigo_exporter directory from addons folder and install it again.
What OS are you using? Do you install it manually (zip) or by installer?

That thread is more than 2 years old, so it is very good to see that this is being worked on again. Thanks @MZ!
In the above mentioned thread I provided some feedback on what really needs to be updated in the Blendigo exporter.
The edits I made were very painful because Blendigo does not keep track or use the ID's that are provided in the .igs scene file. That makes it's code really fragile!
There are other areas where Indigo and Blender have developed but Blendigo has not been able to take advantage of these developments.

Edit:
This thread discusses some of the changes that I made too the code and improvements that are loooong overdue.

Hi MZ,
I am using Windows 10 64Bit and recent Blender 2.79.
I deleted the indigo_exporter directory and installed it again. I tried the 2.79-folder in the App Data folder, as well as the Program-Folder, where Blender is located. I always get the same error, the scene was working well before. A screencap of the console is attached.
Thanks!!

That thread is more than 2 years old, so it is very good to see that this is being worked on again. Thanks @MZ!
In the above mentioned thread I provided some feedback on what really needs to be updated in the Blendigo exporter.
The edits I made were very painful because Blendigo does not keep track or use the ID's that are provided in the .igs scene file. That makes it's code really fragile!
There are other areas where Indigo and Blender have developed but Blendigo has not been able to take advantage of these developments.

Edit:
This thread discusses some of the changes that I made too the code and improvements that are loooong overdue.

From what I've understood, , MZ has resolved a few of these things - mediums have their own panel, max SS value has been increased, Null and FastSSS material support added, etc. He also rewrote the addon without the use of that extension framework.

Some of the requests are obviously still valid, maybe we should do an updated wishlist?

I think there is still bug present when "skip writing meshes" is enabled.

Currently most problematic for me is export time when there are lots of objects inside scene (just linked geometry with igm proxies) and particle systems. I can prepare scene to test, but need a while.